Risk Factors for Asthma Exacerbation and Treatment Failure in Adults and Adolescents with Well-controlled Asthma during Continuation and Step-Down Therapy

Multivariate analysis and data mining help predict asthma exacerbations

BACKGROUND

Work-related asthma has become a highly prevalent occupational lung disorder.

OBJECTIVE

Our study aims to evaluate occupational exposure as a predictor for asthma exacerbation.

METHOD

We performed a retrospective evaluation of 584 consecutive patients diagnosed and treated for asthma between October 2017 and December 2019 in four clinics from Western Romania. We evaluated the enrolled patients for their asthma control level by employing the Asthma Control Test (ACT < 20 represents uncontrolled asthma), the medical record of asthma exacerbations, occupational exposure, and lung function (i.e. spirometry). Then, we used statistical and data mining methods to explore the most important predictors for asthma exacerbations.

RESULTS

We identified essential predictors by calculating the odds ratios (OR) for the exacerbation in a logistic regression model. The average age was 45.42 ± 11.74 years (19-85 years), and 422 (72.26%) participants were females. 42.97% of participants had exacerbations in the past year, and 31.16% had a history of occupational exposure. In a multivariate model analysis adjusted for age and gender, the most important predictors for exacerbation were uncontrolled asthma (OR 4.79, p < .001), occupational exposure (OR 4.65, p < .001), and lung function impairment (FEV1 < 80%) (OR 1.15, p = .011). The ensemble machine learning experiments on combined patient features harnessed by our data mining approach reveal that the best predictor is professional exposure, followed by ACT.

CONCLUSIONS

Machine learning ensemble methods and statistical analysis concordantly indicate that occupational exposure and ACT < 20 are strong predictors for asthma exacerbation.

Expert panel consensus recommendations on the utilization of nebulized budesonide for managing asthma and COPD in both stable and exacerbation stages in Thailand

OBJECTIVE

This study investigated the utilization of nebulized budesonide for acute asthma and COPD exacerbations as well as for maintenance therapy in adults.

DATA SOURCES

We conducted a search on PubMed for nebulized budesonide treatment.

SELECTED STUDIES

Selecting all English-language papers that utilize Mesh phrases "asthma," "COPD," "budesonide," "nebulized," "adult," "exacerbation," and "maintenance" without temporal restrictions, and narrowing down to clinical research such as RCTs, observational studies, and real-world studies.

RESULTS

Analysis of 25 studies was conducted to assess the effectiveness of nebulized budesonide in asthma (n = 10) and COPD (n = 15). The panel in Thailand recommended incorporating nebulized budesonide as an additional or alternative treatment option to the standard of care and systemic corticosteroids (SCS) based on the findings.

CONCLUSION

Nebulized budesonide is effective and well-tolerated in treating asthma and COPD, with less systemic adverse effects compared to systemic corticosteroids. High-dose nebulized budesonide can enhance clinical outcomes for severe and mild exacerbations with slow systemic corticosteroid response. Nebulized budesonide can substitute systemic corticosteroids in some situations.

Prevalence and clinical implications of respiratory viruses in asthma during stable disease state and acute attacks: Protocol for a meta-analysis

INTRODUCTION

Viruses are detected in over 50% of acute asthma attacks and in a notable proportion of patients with asthma during stable disease state They are associated with worse outcomes. We will conduct a series of systematic reviews and meta-analyses to quantify the prevalence and clinical burden of various respiratory viruses in stable asthma and acute asthma attacks. In addition, we will assess the viral loads of respiratory viruses during stable and acute asthma, to explore whether viral load could differentiate attacks triggered by viruses versus those where viruses are present as "innocent bystanders".

MATERIALS AND METHODS

Based on a prospectively registered protocol (PROSPERO, ID: CRD42023375108) and following standard methodology recommended by Cochrane, we will systematically search Medline/PubMed, EMBASE, the Cochrane Library and relevant conference proceedings for studies assessing the prevalence or clinical burden of respiratory viruses in asthma. Methodological rigour of the included studies will be appraised using a tool specific for prevalence studies and the Newcastle-Ottawa Scale respectively. In anticipation of significant clinical and methodological heterogeneity, we will conduct random effect meta-analyses. For evaluating the prevalence of viruses, we will perform meta-analyses of proportions using the inverse variance method, and the Freeman-Tukey transformation. We will conduct meta-regression analyses for exploring heterogeneity.

CONCLUSION

We envisage that these systematic reviews and meta-analyses will quantify the prevalence and burden of respiratory viruses in stable and acute asthma and will drive future research and clinical practice.

Mechanical forces suppress antiviral innate immune responses from asthmatic airway epithelial cells following rhinovirus infection

Bronchoconstriction is the main physiological event in asthma, which leads to worsened clinical symptoms and generates mechanical stress within the airways. Virus infection is the primary cause of exacerbations in people with asthma, however, the impact that bronchoconstriction itself on host antiviral responses and viral replication is currently not well understood. Here we demonstrate how mechanical forces generated during bronchoconstriction may suppress antiviral responses at the airway epithelium without any difference in viral replication. Primary bronchial epithelial cells from donors with asthma were differentiated at the air-liquid interface. Differentiated cells were apically compressed (30 cmH2O) for 10 min every hour for 4 days to mimic bronchoconstriction. Two asthma disease models were developed with the application of compression, either before ("poor asthma control model," n = 7) or following ("exacerbation model," n = 4) rhinovirus (RV) infection. Samples were collected at 0, 24, 48, 72, and 96 h postinfection (hpi). Viral RNA, interferon (IFN)-β, IFN-λ, and host defense antiviral peptide gene expressions were measured along with IFN-β, IFN-λ, TGF-β2, interleukin-6 (IL-6), and IL-8 protein expression. Apical compression significantly suppressed RV-induced IFN-β protein from 48 hpi and IFN-λ from 72 hpi in the poor asthma control model. There was a nonsignificant reduction of both IFN-β and IFN-λ proteins from 48 hpi in the exacerbation model. Despite reductions in antiviral proteins, there was no significant change in viral replication in either model. Compressive stress mimicking bronchoconstriction inhibits antiviral innate immune responses from asthmatic airway epithelial cells when applied before RV infection.NEW & NOTEWORTHY Bronchoconstriction is the main physiological event in asthma, which leads to worsened clinical symptoms and generates mechanical stress within the airways. Virus infection is the primary cause of exacerbations in people with asthma, however, the impact of bronchoconstriction on host antiviral responses and viral replication is unknown. We developed two disease models, in vitro, and found suppressed IFN response from cells following the application of compression and RV-A1 infection. This explains why people with asthma have deficient IFN response.

Revisiting asthma pharmacotherapy: where do we stand and where do we want to go?

Several current guidelines/strategies outline a treatment approach to asthma, which primarily consider the goals of improving lung function and quality of life and reducing symptoms and exacerbations. They suggest a strategy of stepping up or down treatment, depending on the patient's overall current asthma symptom control and future risk of exacerbation. While this stepwise approach is undeniably practical for daily practice, it does not always address the underlying mechanisms of this heterogeneous disease. In the last decade, there have been attempts to improve the treatment of severe asthma, such as the addition of a long-acting antimuscarinic agent to the traditional inhaled corticosteroid/long-acting β2-agonist treatment and the introduction of therapies targeting key cytokines. However, despite such strategies several unmet needs in this population remain, motivating research to identify novel targets and develop improved therapeutic and/or preventative asthma treatments. Pending the availability of such therapies, it is essential to re-evaluate the current conventional "one-size-fits-all" approach to a more precise asthma management. Although challenging, identifying "treatable traits" that contribute to respiratory symptoms in individual patients with asthma may allow a more pragmatic approach to establish more personalised therapeutic goals.

Effects of Ambient Air Pollutants on Hospital Admissions among Children Due to Asthma and Wheezing-Associated Lower Respiratory Infections in Mysore, India: A Time Series Study

Air pollutants are known to trigger asthma and wheezing-associated lower respiratory infections in children, but evidence regarding their effect on hospital admissions in India is limited. We conducted a time-series study over a period of five years to assess the role of ambient air pollutants in daily asthma-related hospital admissions in children in Mysore, India. Daily asthma and wheeze (associated with lower respiratory infections) admissions were modelled using a generalised additive model (GAM) to examine the non-linear effects and generalised linear models (GLM) for linear effects, if any. Models were adjusted by day of the week and lag days, with smooth terms for time, maximum temperature, and relative humidity, and they were stratified by sex and age group. Of the 362 children admitted, more than 50% were boys, and the mean age was 5.34 years (±4.66). The GAMs showed non-linear associations between NO2, PM2.5, and NH3. For example, a 10 µgm-3 (or 10%) increase in NO2 increased admissions by 2.42. These non-linear effects were more pronounced in boys. A linear effect was detected for PM10 with a relative risk (95% CI) of 1.028, 1.013, and 1.043 with admission. Further research is needed to explore whether these findings can be replicated in different cities in India. Air pollution needs to be controlled, and policies that focus on lower cut-off levels for vulnerable populations are necessary.

Machine learning for prediction of asthma exacerbations among asthmatic patients: a systematic review and meta-analysis

BACKGROUND

Asthma exacerbations reduce the patient's quality of life and are also responsible for significant disease burdens and economic costs. Machine learning (ML)-based prediction models have been increasingly developed to predict asthma exacerbations in recent years. This systematic review and meta-analysis aimed to identify the prediction performance of ML-based prediction models for asthma exacerbations and address the uncertainty of whether modern ML methods could become an alternative option to predict asthma exacerbations.

METHODS

PubMed, Cochrane Library, EMBASE, and Web of Science were searched for studies published up to December 15, 2022. Studies that applied ML methods to develop prediction models for asthma exacerbations among asthmatic patients older than five years and were published in English were eligible. The prediction model risk of bias assessment tool (PROBAST) was utilized to estimate the risk of bias and the applicability of included studies. Stata software (version 15.0) was used for the random effects meta-analysis of performance measures. Subgroup analyses stratified by ML methods, sample size, age groups, and outcome definitions were conducted.

RESULTS

Eleven studies, including 23 prediction models, were identified. Most of the studies were published in recent three years. Logistic regression, boosting, and random forest were the most used ML methods. The most common important predictors were systemic steroid use, short-acting beta2-agonists, emergency department visit, age, and exacerbation history. The overall pooled area under the curve of the receiver operating characteristics (AUROC) of 11 studies (23 prediction models) was 0.80 (95% CI 0.77-0.83). Subgroup analysis based on different ML models showed that boosting method achieved the best performance, with an overall pooled AUROC of 0.84 (95% CI 0.81-0.87).

CONCLUSION

This study identified that ML was the potential tool to achieve great performance in predicting asthma exacerbations. However, the methodology within these models was heterogeneous. Future studies should focus on improving the generalization ability and practicability, thus driving the application of these models in clinical practice.

A prediction model for asthma exacerbations after stopping asthma biologics

BACKGROUND

Little is known regarding the prediction of the risks of asthma exacerbation after stopping asthma biologics.

OBJECTIVE

To develop and validate a predictive model for the risk of asthma exacerbations after stopping asthma biologics using machine learning models.

METHODS

We identified 3057 people with asthma who stopped asthma biologics in the OptumLabs Database Warehouse and considered a wide range of demographic and clinical risk factors to predict subsequent outcomes. The primary outcome used to assess success after stopping was having no exacerbations in the 6 months after stopping the biologic. Elastic-net logistic regression (GLMnet), random forest, and gradient boosting machine models were used with 10-fold cross-validation within a development (80%) cohort and validation cohort (20%).

RESULTS

The mean age of the total cohort was 47.1 (SD, 17.1) years, 1859 (60.8%) were women, 2261 (74.0%) were White, and 1475 (48.3%) were in the Southern region of the United States. The elastic-net logistic regression model yielded an area under the curve (AUC) of 0.75 (95% confidence interval [CI], 0.71-0.78) in the development and an AUC of 0.72 in the validation cohort. The random forest model yielded an AUC of 0.75 (95% CI, 0.68-0.79) in the development cohort and an AUC of 0.72 in the validation cohort. The gradient boosting machine model yielded an AUC of 0.76 (95% CI, 0.72-0.80) in the development cohort and an AUC of 0.74 in the validation cohort.

CONCLUSION

Outcomes after stopping asthma biologics can be predicted with moderate accuracy using machine learning methods.

Racial and Ethnic Minorities at the Highest Risk of Uncontrolled Moderate-to-Severe Asthma: A United States Electronic Health Record Analysis

Purpose

The identification of risk factors associated with uncontrolled moderate-to-severe asthma is important to improve asthma outcomes. Aim of this study was to identify risk factors for uncontrolled asthma in United States cohort using electronic health record (EHR)-derived data.

Patients and Methods

In this retrospective real-world study, de-identified data of adolescent and adult patients (≥12 years old) with moderate-to-severe asthma, based on asthma medications within 12 months prior to asthma-related visit (index date), were extracted from the Optum^® Humedica EHR. The baseline period was 12 months prior to the index date. Uncontrolled asthma was defined as ≥2 outpatient oral corticosteroid bursts for asthma or ≥2 emergency department visits or ≥1 inpatient visit for asthma. A Cox proportional hazard model was applied.

Results

There were 402,403 patients in the EHR between January 1, 2012, and December 31, 2018, who met the inclusion criteria and were analyzed. African American (AA) race (hazard ratio [HR]: 2.08), Medicaid insurance (HR: 1.71), Hispanic ethnicity (HR: 1.34), age of 12 to <18 years (HR 1.20), body mass index of ≥35 kg/m² (HR: 1.20), and female sex (HR 1.19) were identified as risk factors associated with uncontrolled asthma (P < 0.001). Comorbidities characterized by type 2 inflammation, including a blood eosinophil count of ≥300 cells/μL (as compared with eosinophil <150 cells/μL; HR: 1.40, P < 0.001) and food allergy (HR: 1.31), were associated with a significantly higher risk of uncontrolled asthma; pneumonia was also a comorbidity associated with an increased risk (HR: 1.35) of uncontrolled asthma. Conversely, allergic rhinitis (HR: 0.84) was associated with a significantly lower risk of uncontrolled asthma.

Conclusion

This large study demonstrates multiple risk factors for uncontrolled asthma. Of note, AA and Hispanic individuals with Medicaid insurance are at a significantly higher risk of uncontrolled asthma versus their White, non-Hispanic counterparts with commercial insurance.

Asthma exacerbations: the Achilles heel of asthma care

Asthma exacerbations significantly impact millions of patients worldwide to pose large disease burdens on affected patients, families, and health-care systems. Although numerous environmental factors cause asthma exacerbations, viral respiratory infections are the principal triggers. Advances in the pathophysiology of asthma have elucidated dysregulated protective immune responses and upregulated inflammation that create susceptibility and risks for exacerbation. Biologics for the treatment of severe asthma reduce rates of exacerbations and identify specific pathways of inflammation that contribute to altered pathophysiology, novel therapeutic targets, and informative biomarkers. Major steps to prevent exacerbations include the identification of molecular pathways whose blockage will prevent asthma attacks safely, predictably, and effectively.

Phenotyping, Precision Medicine, and Asthma

The traditional one-size-fits all approach based on asthma severity is archaic. Asthma is a heterogenous syndrome rather than a single disease entity. Studies evaluating observable characteristics called phenotypes have elucidated this heterogeneity. Asthma clusters demonstrate overlapping features, are generally stable over time and are reproducible. What the identification of clusters may have failed to do, is move the needle of precision medicine meaningfully in asthma. This may be related to the lack of a straightforward and clinically meaningful way to apply what we have learned about asthma clusters. Clusters are based on both clinical factors and biomarkers. The use of biomarkers is slowly gaining popularity, but phenotyping based on biomarkers is generally greatly underutilized even in subspecialty care. Biomarkers are more often used to evaluate type 2 (T2) inflammatory signatures and eosinophils (sputum and blood), fractional exhaled nitric oxide (FeNO) and serum total and specific immunoglobulin (Ig) E reliably characterize the underlying inflammatory pathways. Biomarkers perform variably and clinicians must be familiar with their advantages and disadvantages to accurately apply them in clinical care. In addition, it is increasingly clear that clinical features are critical in understanding not only phenotypic characterization but in predicting response to therapy and future risk of poor outcomes. Strategies for asthma management will need to leverage our knowledge of biomarkers and clinical features to create composite scores and risk prediction tools that are clinically applicable. Despite significant progress, many questions remain, and more work is required to accurately identify non-T2 biomarkers. Adoption of phenotyping and more consistent use of biomarkers is needed, and we should continue to encourage this incorporation into practice.

Ambient Air Pollution and Risk of Admission Due to Asthma in the Three Largest Urban Agglomerations in Poland: A Time-Stratified, Case-Crossover Study

Ambient air pollution in urban areas may trigger asthma exacerbations. We carried out a time-series analysis of the association between the concentrations of various air pollutants and the risk of hospital admission due to asthma over 7 days from exposure. We used distributed lag nonlinear models to analyze data gathered between 2010 and 2018 in the three largest urban agglomerations in Poland. Overall, there were 31,919 asthma hospitalizations. Over 7 days since exposure, the rate ratio (95%CI) for admission per 10 µg/m3 was 1.013 (1.002–1.024) for PM10; 1.014 (1.000–1.028) for PM2.5; 1.054 (1.031–1.078) for NO2; and 1.044 for SO2 (95%CI: 0.986–1.104). For all pollutants, the risk of admission was the greatest on the day of exposure (day 0), decreased below baseline on days 1 and 2, and then increased gradually up to day 6. The proportions (95%CI) of hospitalizations attributable to air pollution were 4.52% (0.80%–8.14%) for PM10; 3.74% (0.29%–7.11%) for PM2.5; 16.4% (10.0%–21.8%) for NO2; and 2.50% (−0.75%–5.36%) for SO2. In conclusion, PM2.5, PM10, NO2, and SO2 pollution was associated with an increased risk of hospital admission due to asthma in the three largest urban agglomerations in Poland over nine years.

Blood miRNAs Are Linked to Frequent Asthma Exacerbations in Childhood Asthma and Adult COPD

MicroRNAs have been independently associated with asthma and COPD; however, it is unclear if microRNA associations will overlap when evaluating retrospective acute exacerbations. Objective: We hypothesized that peripheral blood microRNAs would be associated with retrospective acute asthma exacerbations in a pediatric asthma cohort and that such associations may also be relevant to acute COPD exacerbations. Methods: We conducted small-RNA sequencing on 374 whole-blood samples from children with asthma ages 6-14 years who participated in the Genetics of Asthma in Costa Rica Study (GACRS) and 450 current and former adult smokers with and without COPD who participated in the COPDGene study. Measurements and Main Results: After QC, we had 351 samples and 649 microRNAs for Differential Expression (DE) analysis between the frequent (n = 183) and no or infrequent exacerbation (n = 168) groups in GACRS. Fifteen upregulated miRs had odds ratios (OR) between 1.22 and 1.59 for a doubling of miR counts, while five downregulated miRs had ORs between 0.57 and 0.8. These were assessed for generalization in COPDGene, where three of the upregulated miRs (miR-532-3p, miR-296-5p, and miR-766-3p) and two of the downregulated miRs (miR-7-5p and miR-451b) replicated. Pathway enrichment analysis showed MAPK and PI3K-Akt signaling pathways were strongly enriched for target genes of DE miRNAs and miRNAs generalizing to COPD exacerbations, as well as infection response pathways to various pathogens. Conclusion: miRs (451b; 7-5p; 532-3p; 296-5p and 766-3p) associated with both childhood asthma and adult COPD exacerbations may play a vital role in airflow obstruction and exacerbations and point to shared genomic regulatory machinery underlying exacerbations in both diseases.

Longitudinal asthma exacerbation phenotypes in the Korean childhood asthma study cohort

BACKGROUND

Asthma exacerbation (AE) leads to social and economic costs and long-term adverse outcomes. We aimed to predict exacerbation-prone asthma (EPA) in children.

METHODS

The Korean childhood Asthma Study (KAS) is a prospective nationwide pediatric asthma cohort of children aged 5-15 years followed every 6 months. Patients with AE during the 6 months prior to all three visits, with AE prior to one or two visits, and without AE prior to any visit were defined as having EPA, exacerbation-intermittent asthma (EIA), and exacerbation-resistant asthma (ERA), respectively. Risk factors and prediction models of EPA were explored.

RESULTS

Of the 497 patients who completed three visits, 42%, 18%, and 15% had exacerbations prior to visits 1, 2, and 3 and 5%, 47%, and 48% had EPA, EIA, and ERA, respectively. Univariate and multivariable logistic regression revealed forced expiratory volume in 1 s (FEV1) z-score, forced vital capacity (FVC) z-score, white blood cell (WBC) count, and asthma control test (ACT) score as relevant EPA risk factors. The EPA prediction model comprised FVC z-score, WBC count, ACT score, sex, and parental education level (area under the receiver operating characteristic curve [AUROC] 0.841 [95% confidence interval (CI): 0.728-0.954]).

CONCLUSION

With appropriate management, AE decreases over time, but persistent AEs may occur. Apart from asthma control level, baseline lung function and WBC count predicted EPA.

Does the Use of Asthma-Controller Medication in Accordance with Guidelines Reduce the Incidence of Acute Exacerbations and Healthcare Costs?

Background

In asthma, consistent control of chronic airway inflammation is crucial, and the use of asthma-controller medication has been emphasized. Our purpose in this study is to compare the incidence of acute exacerbation and healthcare costs related to the use of asthma-controller medication.

Methods

By using data collected by the National Health Insurance Review and Assessment Service, we compared one-year clinical outcomes and medical costs from July 2014 to June 2015 (follow-up period) between two groups of patients with asthma who received different prescriptions for recommended asthma-controller medication (inhaled corticosteroids or leukotriene receptor antagonists) at least once from July 2013 to June 2014 (assessment period).

Results

There were 51,757 patients who satisfied our inclusion criteria. Among them, 13,702 patients (26.5%) were prescribed a recommended asthma-controller medication during the assessment period. In patients using a recommended asthma-controller medication, the frequency of acute exacerbations decreased in the follow-up period, from 2.7% to 1.1%. The total medical costs of the controller group decreased during the follow-up period compared to the assessment period, from $3,772,692 to $1,985,475. Only 50.9% of patients in the controller group used healthcare services in the follow-up period, and the use of asthma-controller medication decreased in the follow-up period.

Conclusion

Overall, patients using a recommended asthma-controller medication showed decreased acute exacerbation and reduced total healthcare cost by half.

Hospital admission rate in children and adolescents with mild persistent asthma

INTRODUCTION

The health and financial burden of mild-persistent asthma has been poorly investigated.

OBJECTIVE

Our aim was to compare the rate of hospital admissions that have occurred during the preceding year between children and adolescents with current mild-persistent (MP) and moderate-severe (MS) asthma.

METHODS

We screened children and adolescents with asthma at eight outpatient clinics. The inclusion criteria were asthma diagnosis, age from 6 to 18 years and follow-up with a physician during the preceding 6 months. Subjects answered standardized questionnaires and underwent spirometry.

RESULTS

We enrolled 220 MP and 102 MS asthmatic subjects. The proportion of subjects with HA during the preceding year was similar between MP and MS asthma groups (7% vs. 7%; p = .89). Symptoms score and the financial values spent by the family in the care of asthma were lower in MP asthma as compared with MS asthma group (asthma control questionnaire score 0.7 [0.3-1.0) vs. 2.0 [1.1-2.5]; p < .01) (asthma expenses in USD 13 [2-43] vs. 28 [10-83]; p < .01). The frequency of subjects using inhaled corticosteroids maintenance therapy was lower in the MP asthma group as compared with the MS asthma group (54% vs. 100%; p < .01).

CONCLUSION

We conclude that the frequency of hospital admissions that have occurred during the preceding year was similar between subjects with current MP and MS asthma. Symptoms score and the financial values spent by the family in the care of asthma were lower in the MP asthma group.

Persistence of Eosinophilic Asthma Endotype and Clinical Outcomes: A Real-World Observational Study

Purpose

Eosinophil count elevations are predictive of adverse outcomes in patients with asthma, yet little is known regarding longitudinal eosinophil patterns and their association with clinical outcomes. The goal of this study was to assess associations between longitudinal persistence of eosinophil elevations and both clinical outcomes and health care resource utilization (HCRU).

Methods

Data were extracted from 2 databases in the United Kingdom. Patients included were aged ≥13 years, had active asthma, and had ≥3 blood eosinophil count (BEC) recordings. Patients were categorized by BEC as: never high (all BEC ≤300 cells/µL), intermittently high (≥1 BEC >300 cells/µL but <75% of BEC >300 cells/µL), or persistently high (≥75% of BEC >300 cells/µL). Asthma exacerbations, asthma control (risk domain, overall, and full), and HCRU were evaluated for 12 months after the last BEC.

Results

The study population comprised 148,021 patients. Persistently high, intermittently high, and never high eosinophil patterns were detected in 13.6%, 40.5%, and 45.9% of patients, respectively. Patients with ≥1 elevated BEC were at greater risk for severe asthma exacerbations, regardless of whether the elevation was persistent (rate ratio [RR]: 1.28 [95% CI 1.24–1.33]; P < 0.001) or intermittent (RR: 1.24 [95% CI 1.21–1.27]; P < 0.001), compared with patients with no eosinophil elevations. Full asthma control was achieved by <25% of patients across eosinophil pattern groups, and HCRU did not appreciably differ, although patients with persistently high BEC had the shortest hospital stay duration among the groups.

Conclusion

These data suggest that elevated blood eosinophils, regardless of persistency, signify increased risk of severe asthma exacerbations.

Step-up and step-down approaches in the treatment of asthma

Introduction: Significant intraindividual and temporal variability in symptom control is a feature of asthma that requires careful monitoring and the need to periodically review and adjust therapy. Both NHLBI/NAEPP and GINA offer helpful algorithms for a stepping approach to asthma.Areas covered: The problems arisen in applying the stepwise approach to the treatment of asthma proposed by NHLBI/NAEPP and GINA algorithms and their possible alternatives.Expert opinion: The current therapeutic stepping approach to asthma, which takes into account lung function, symptoms and quality of life, is certainly useful, but it does not consider the underlying mechanisms. Furthermore, patient's overestimation or underestimation of the severity of the disease and differences in the opinions on the level of asthma control required between patients and physicians and also between physicians in both primary care and specialist settings are common and may negatively affect asthma control and future risks. A reassessment of the conventional stepping approach to management of asthma is now needed. A pragmatic approach that sets therapeutic goals for each individual and associates them with the treatable traits of asthma which, when therapeutically targeted, will in many cases help to achieve the goals, seems more reasonable than the present stepping approach.

Exacerbation-Prone Asthma: A Biological Phenotype or a Social Construct

Asthma is a complex syndrome with multiple phenotypes and endotypes. Asthma exacerbations are not only the clearest indictor of the morbidity of asthma and of the risk for mortality due to asthma, but also comprise a significant amount of the cost to care for poorly controlled asthma. There continues to be significant disparity in the prevalence, mortality, and morbidity due to asthma. Patients with asthma who suffer recurrent exacerbations are considered to have exacerbation-prone asthma (EPA). Efforts to characterize patients with frequent exacerbations show that the etiology is likely multifactorial. Research to determine the intrinsic risk factors for EPA include studies of both genetic and inflammatory biomarkers. External factors contributing to exacerbations have been extensively reviewed and include viral infection, environmental exposures, air pollution, and psychosocial and economic barriers to optimizing health. It is likely that EPA occurs when patients who have an increased underlying intrinsic/biological risk are placed in a given exposome (environments with a variety of exposures and triggers including allergens, pollution, stress, barriers, and occupational exposures). It is the social construct combined with underlying biology that frequently drives an EPA phenotype.

Pragmatic Randomized Controlled Trial for Stepping Down Asthma Controller Treatment in Patients Controlled with Low-Dose Inhaled Corticosteroid and Long-Acting β2-Agonist: Step-Down of Intervention and Grade in Moderate Asthma Study

BACKGROUND

Current asthma guidelines recommend stepping down controller treatment when the condition is well-controlled for a certain time. However, the optimal step-down strategy for well-controlled patients receiving a low-dose inhaled corticosteroid (ICS) with a long-acting β₂-agonist (LABA) remains unclear.

OBJECTIVE

This study was a randomized, open-label, three-arm, parallel pragmatic trial comparing two kinds of step-down approaches for maintaining treatment.

METHODS

Adults with asthma who were aged 18 years or older, and who had been stable with low-dose ICS/LABA for at least 3 months, were enrolled. Subjects (n = 225) were randomly allocated into one of three groups (maintaining low-dose ICS/LABA [G1], discontinuing LABA [G2], and reducing ICS/LABA to once daily [G3]), and were observed for 6 months. The primary end point was a change in Asthma Control Test (ACT) scores between randomization and the final 6-month follow-up.

RESULTS

The change in ACT was analyzed in the per-protocol population; noninferiority was not demonstrated in either step-down group compared with the maintenance group (95% confidence interval of the difference, G2 vs G1 = -1.40-0.55; G3 vs G1 = -1.19-0.77). Although over 90% of patients were fine, higher rates of treatment failure were observed in step-down groups (G1: 0%; G2: 9.46%; and G3: 9.09%; P = .027). There were no significant differences between step-down approaches in terms of ACT change or treatment failure.

CONCLUSIONS

Both step-down methods were not noninferior to maintenance of treatment. Step-down therapy can be attempted when patients are stable, but appropriate monitoring and supervision are necessary with precautions regarding loss of disease control.

A step-down experience in asthma treatment: a retrospective cohort study

BACKGROUND

According to recent guidelines; patients with controlled asthma who are stable for at least three months and don't have risk factor should be considered for step down.

OBJECTIVE

To evaluate our step down attempts and affecting factors.

METHODS

This study was a retrospective-cohort study of patients with asthma who were followed up in our clinic for at least one year. Sociodemographic, phenotypic, clinical features and number of step-down attempts were recorded from the files. Step down was tried in well controlled patients and considered as successful whether descending step was maintained or a lower step was reached until the last visit.

RESULTS

A total of 239 patients (196 F/43 M) with a mean age of 51.54 ± 15.29 years were included in the study. Step-down attempt was performed in 44.8% (n = 107) of the patients and % 74.8 (n = 80) of them were successful. Factors related to failure were lower level of education, allergic comorbidity (p = 0.04) and female gender (p = 0.04). Risk of failure was 3.45 and 1.84 times higher than university graduates in high school and primary school graduates, respectively. The probability of failure in step down was 3.38 times higher in patients with allergic comorbidity, and it was 3.92 times more likely in women than men.

CONCLUSIONS

Our results showed that the step down attempt could be performed in patients receiving treatment from all steps. In addition, treatment of allergic comorbidities and increased level of education, may make a step down attempt more successful.

Asthma attacks in children are always preceded by poor asthma control: myth or maxim?

Some, but not all, asthma exacerbations in children are preceded by poor asthma control https://bit.ly/3muIy6h.

Predictive factors of response to inhaled corticosteroids in newly diagnosed asthma: A real-world observational study

BACKGROUND

Asthma is characterized by chronic airway inflammation, and inhaled corticosteroids (ICSs) have been recommended as first-line treatment. However, response to ICS treatment is various, and the prediction of response to ICSs is still difficult, especially in individuals with newly diagnosed asthma.

OBJECTIVE

To assess the clinical factors and biomarkers associated with response to ICSs in newly diagnosed asthma.

METHODS

A total of 150 ICS-naive patients with newly diagnosed asthma in the allergy clinic of a single tertiary hospital in Korea from January 2014 to January 2019 were included in this study. All patients initially received moderate-dose ICSs and were treated for more than 1 year. We compared the clinical characteristics and parameters between patients with and without acute exacerbation (AE) during the study period.

RESULTS

In this study, 99 patients had no AE (stable asthma group), and 51 patients presented with more than 1 AE (unstable asthma group). The mean (SD) blood eosinophil count (635.7 [780.3] × 10³/μL vs 373.4 [266.8] × 10³/μL, P = .003) and sputum eosinophil count (15.2% [23.9%] vs 8.3% [15.4%], P = .051) were higher and the sputum neutrophil count (42.9% [35.1%] vs 61.3% [35.1%], P = .057) was lower in the stable asthma group than in the unstable asthma group.

CONCLUSION

High blood and sputum eosinophil counts can predict a good response to ICS treatment in terms of prevention of AE in individuals with newly diagnosed asthma. The sputum neutrophil count may be an effective predictor of response to ICSs, even though additional studies must be conducted.

The Asthma Controller Step-down Yardstick

Asthma guidelines recommend a control-based approach to disease management in which the assessment of impairment and risk is linked to step-based therapy. Using this model, controller treatment is adjusted-upward or downward-according to a patient's level of asthma control over time. Strategies for stepping up controller therapy are well described, and the adult and pediatric Asthma Yardsticks provide operational recommendations based on patient profiles. Strategies for stepping down controller treatment are less clear, although stepping down to the minimum effective therapy is important and should be considered when a patient's asthma has been well controlled for an adequate period as defined by risk and impairment. This Yardstick presents recommendations for when and how to step down asthma controller therapy according to guideline-defined control levels. The objective is to provide clinicians who treat patients with asthma with a practical and clinically relevant framework for implementing a step-down in controller therapy.

A Simple Score for Future Risk Prediction in Patients with Controlled Asthma Who Undergo a Guidelines-Based Step-Down Strategy

BACKGROUND

The minimum controlling dose of treatment must be established in patients with asthma, but the outcome of step-down is unpredictable.

OBJECTIVE

To identify factors associated with risk of control loss when stepping down asthma treatment and to develop a score to predict this risk.

METHODS

A prospective, multicenter study including adults with well-controlled asthma was performed. Treatment was stepped up or stepped down over a 12-month period to maintain asthma control. We determined associations between clinical and functional variables and step-down failure. Finally, we derived a score to predict loss of control in 1 cohort and validated it in an independent cohort.

RESULTS

The derivation cohort consisted of 228 patients; 218 completed at least 1 step-down episode and a total of 495 step-down episodes were evaluated. A medical-record documented postbronchodilator spirometry result of <70% forced expiratory volume in 1 second (FEV₁)/forced vital capacity (odds ratio [OR] = 2.08; 95% confidence interval [CI]: 1.26-3.43), current FEV₁ < 80% (OR = 1.80; 95% CI: 1.03-3.14), ≥1 severe exacerbation in the previous 12 months (OR = 2.43; 95% CI: 1.48-4.01), and Asthma Control Test score < 25 (OR = 2.30; 95% CI: 1.35-3.92) were independently associated with failure. The score showed an area under the curve of 0.690 (95% CI: 0.633-0.747; P < .05) in the derivation cohort and 0.76 (95% CI: 0.643-0.882; P < .001) in a validation cohort of 114 patients. A score <4.5 implies a low risk of failure (<20%), whereas a score >8 implies a high risk (>40%).

CONCLUSION

This score can facilitate the prediction of step-down failure before medication taper in patients with well-controlled asthma.